Mina is trying to focus on her job as a flight attendant, not the problems of her five-year-old daughter back home or the fissures in her marriage. But the plane has barely taken off when Mina receives a chilling note from an anonymous passenger, someone intent on ensuring the plane never reaches its destination. Someone who needs Mina's assistance and who knows exactly how to make her comply. It's 20 hours to landing. A lot can happen in 20 hours....

Pete Riley answers the door one morning and lets in a parent's worst nightmare. On his doorstep is Miles Lambert, a stranger who breaks the devastating news that Pete's son, Theo, isn't actually his son - he is the Lamberts', switched at birth by an understaffed hospital while their real son was sent home with Miles and his wife, Lucy. For Pete, his partner Maddie, and the little boy they've been raising for the past two years, life will never be the same again.

Anna Hart is a seasoned missing persons detective in San Francisco with far too much knowledge of the darkest side of human nature. When tragedy strikes her personal life, Anna, desperate and numb, flees to the Northern California village of Mendocino to grieve. She lived there as a child with her beloved foster parents, and now she believes it might be the only place left for her. Yet the day she arrives, she learns that a local teenage girl has gone missing.

In Gold Coast, Long Island, everything from the expensive downtown shops to the manicured beaches, to the pressed uniforms of Jill Newman and her friends, looks perfect. But as Jill found out three years ago, nothing is as it seems. Freshman year Jill's best friend, the brilliant, dazzling Shaila Arnold, was killed by her boyfriend. After that dark night on the beach, Graham confessed, the case was closed, and Jill tried to move on.

New friends Sam, Margaret and Diana are thrilled to be getting out of the city for a girls’ weekend - they’ve bonded over their messy divorces, and every mile on the odometer feels like another step towards putting their exes in the past. But when car trouble halfway into their trip strands them in the most unlikely of mountain towns, they come face-to-face with the hurts and betrayals they were so desperate to leave behind. When Diana doesn't return home after a night out, Sam and Margaret's search for her reveals just how little they know about their friend.